Clicking on Google Books and typing “James Clerk Maxwell” will quickly bring you to A Treatise on Electricity And Magnetism (1873). In this awesome volume, Maxwell synthesizes and thoroughly rationalizes the work of Faraday and other researchers. True, Maxwell’s outer limits were challenged by the Michelson-Morley experiment, which failed to detect the lumeniferous aether that Maxwell’s field theory would seem to require. Albert Einstein’s later counter-intuitive interpretation and the far-out implications of quantum mechanics notwithstanding, Maxwell’s four partial differential equations still unify our understanding of light and electromagnetic radiation as phenomena that occupy a single spectrum.
Maxwell admired and respected those who went before, going back as far as Thales of Miletus. His work primarily built upon experimental results obtained by Charles-Augustin Coulomb and Michael Faraday. Coulomb by chance had discovered that a magnetized needle is deflected when current passes through a nearby conductor. Faraday had built upon this observation, amassing a large amount of experimental data, which he gave to the world along with incisive interpretations that were meaningful to subsequent researchers including Maxwell. Faraday lacked the mathematical expertise as well as the inclination to conceptualize the phenomena that he described so well. Maxwell, with his unifying field theory and equations, can be seen as completing the work of his predecessors, establishing a high plateau of accurate theory, fully quantified.
This line of thought began at King’s College in 1862, where Maxwell found by calculation that electromagnetic force propagates at approximately the speed of light. Maxwell reasoned that the great rate at which both entities traverse vast distances through space could not be regarded as coincidence. The logical conclusion is that light and electromagnetism are actually the same except for frequency.
Maxwell was proficient in experimentation and theorization as well. This was evident in his work on the motion of gas molecules. His approach turned to statistics and probability, previously used more in the social sciences, to analyze these motions. The result was the Maxwell-Boltzmann theory of distribution of molecular energies.
In connection with Maxwell’s idea of the propagation of light and electromagnetic force, Albert Einstein, who kept a portrait of Maxwell on the wall of his study, had this to say:
Since Maxwell’s time, physical reality has been thought of as represented by continuous fields, and not capable of any mechanical interpretation. This change in the conception of reality is the most profound and the most fruitful that physics has experienced since the time of Newton.
The old imagery of electricity as moving through wires like fluid moving through pipes, was overthrown in favor of abstract mathematical models, and this new style of thinking made possible Einstein’s Theory of Relativity and the related but not yet compatible odd notions of quantum mechanics.
michael monostori says
A true mathematical genius.
Another one of our giants of science who very well
should have been held as a rock star of his generation.
Michael says
Nice summary! Sadly, few remember Oliver Heaviside, who actually developed the differential form of Maxwell’s equations as shown here. Maxwell’s original derivation extended to 20 equations, which Heaviside later simplified.
An excellent primer on Maxwell’s life and thought can be found in “The Man Who Changed Everything” by Basil Mahon.
Harry Weston says
It is sad that hardly any mention is ever made of the the contribution that Oliver Heaviside made. It was he that turned Maxwell’s cumbersome 20 or so equations into the succinct form of the four elegant equations that you have shown. ref: “Oliver Heaviside” by Paul Nahin, ISBN 0-8018-6909-9
Derek Dawkins says
Thanks for reminding us of Maxwell’s incomparable contribution to Electromagnetics.
However, can I remind you that the 4 equation expression of electromagnetic fields is Oliver Heaviside’s reduction of Maxwell’s 20 original equations published in the 1873 Treatise.